PaperPanorama
FAQ

Nuclear Theory·nucl-th

Monday·November 24, 2025

3 papers—1 primary·2 cross-listed

All3Primary1Cross-lists2
  1. 01

    [Submitted on 21 Nov 2025]

    Maris polarization in the () reaction

    Yoshiki Chazono

    Proton-induced knockout reactions at intermediate energies provide a clean probe for nuclear clusters. The Maris polarization, which is the effective polarization of a particle inside a nucleus arising from nuclear absorption and spin-orbit coupling, has been used in proton knockout to determine the total angular momentum of the removed protons. However, its manifestation in cluster knockout remains unexplored. We theoretically demonstrated that the Maris polarization can be observed via the vector analyzing power of the proton-induced deuteron knockout (p,pd) reaction in imbalanced kinematics. First, we computed the spin correlation coefficient of p-d elastic scattering, which is an elementary process, to identify suitable kinematics for the Maris polarization. Subsequently, we calculated the values of the (p,pd) reaction at 250 MeV for deuteron-cluster orbits with , , and . The large positive values at p-d scattering angles of are consistent with the experimental data. In the corresponding (p,pd) kinematics, the signs of for and orbits are positive and negative, respectively, indicating effective upward and downward polarizations of the deuterons in the nucleus. The value for orbit lies between those for the other two orbits, which can also be explained by the Maris polarization, with the deuteron being knocked out from regions near the poles of the -axis. These results are nearly independent of the deuteron internal state and the nucleon-nucleon effective interactions adopted. We theoretically demonstrated that the Maris polarization occurs in the (p,pd) reaction under imbalanced kinematics. This work may lead to the establishment of the concept of deuteron-cluster orbit. Further experimental and theoretical studies are required to improve the quantitative understanding of this effect.

    Comments:
    9 pages, 12 figures, resubmitted to Physical Review C
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    2511.16899 [pdf]
    0 citations
  2. 02

    [Submitted on 20 Nov 2025] (cross-list from math.NA)

    Scatter-Limited Hybrid Monte Carlo, Deterministic Transport with Quasi-Monte Carlo Sampling

    Johannes Krotz🇺🇸 · Ryan G. McClarren🇺🇸

    We present a hybrid method for time-dependent particle transport that combines Monte Carlo (MC) estimation with a deterministic discrete ordinates (\(S_N\)) solve, augmented by quasi-Monte Carlo (QMC) sampling. For spatial discretizations, the MC component computes a piecewise-constant (cell-averaged) solution, while the \(S_N\) stage employs bilinear discontinuous finite elements. By hybridizing the formulation, the MC subproblem after a prescribed scatter limit becomes scattering-free, yielding a simple and efficient streaming/attenuation procedure. Between time steps, a simple scatter-free MC step is run to relabel the solution as an MC solution. A key feature of the approach is a tunable parameter \(N_{s}\) that controls how many material collisions are handled in the (Q)MC leg before handing off to the deterministic \(S_N\) solve; \(N_s=0\) recovers a purely uncollided MC leg, while \(N_s>0\) produces multi-scatter hybrids. QMC replaces pseudorandom draws with low-discrepancy points in the existing MC sampling maps, enabling a plug-in adoption within the standard MC code with modest, localized changes. We observe significant accuracy and convergence rate improvements through the use of QMC and practically no additional computational cost, which are generally not seen in comparable non-hybrid solves. We believe the multi-scatter approach provides additional flexibility in terms of parallelization and the choice of deterministic solver.

    Subjects:
    math.NA (math.NA); cs.NA (cs.NA); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
    arXiv:
    2511.16821 [pdf]
    0 citations
  3. 03

    [Submitted on 21 Nov 2025] (cross-list from astro-ph.HE)

    Self-bound quark stars with a first-order two-to-three flavor phase transition

    G. Teruya🇧🇷 · G. Lugones🇧🇷 · A. G. Grunfeld🇦🇷

    We investigate self-bound quark stars in a flavor-dependent quark-mass density-dependent model with an excluded-volume correction. We chart the parameter space at zero pressure to identify self-bound regimes, including parametrizations in which self-bound two-flavor matter undergoes a genuine first-order transition at finite pressure. We construct cold, -equilibrated stellar sequences and compute the corresponding global properties (mass-radius relation, tidal deformability, and moment of inertia). For a wide region of the model parameter space, we find that the onset of a core occurs before the maximum-mass configuration is reached, yielding self-bound hybrid stars that follow the typical strange-quark-star sequence morphology but develop a characteristic kink at along the stellar curves. The excluded-volume parameter controls the stiffness of the equation of state and thus masses, radii, tidal deformabilities, and moments of inertia; intermediate repulsion typically reconciles with current astrophysical constraints. We further identify two equation-of-state-insensitive trends: dimensionless moment of inertia versus compactness and gravitational versus baryonic compactness. These results provide model-guided priors and tools for discriminating between hadronic and self-bound equations of state with multimessenger data.

    Comments:
    15 pages, 11 figures, To appear in Phys. Rev. D
    Subjects:
    High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2511.16874 [pdf]
    PRD(2026)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE